Sempra to build big solar plant north of L.A.

San Diego-based Sempra Generation got approval Tuesday from the Kern County Board of Supervisors for a 200-megawatt solar farm to be built 90 miles north of Los Angeles.

The 960-acre Rosamond Solar project would produce enough electricity for about 76,000 homes a year, the company said.

Sempra is shopping the project around to utilities in California and will not build it until it has a contract in place, said spokesman Scott Crider.

Big for-profit utilities in the state are required to increase the amount of power they get form solar, wind and other renewable sources to fight greenhouse gas emissions.

Although Sempra Generation and San Diego Gas & Electric are both owned by Sempra Energy, a deal between the two is not automatic, Crider said.

"It's certainly more complicated," he said, because of regulations designed to prevent self-serving deals.

Sempra is building side-by-side solar plants, totaling 58 megawatts, in Nevada. It is planning the first 150-megawatt phase of a 600-megawatt solar farm in Arizona.

Those three projects will all supply Pacific Gas & Electric.

Sempra's projects have depended on thin-film photovoltaics, a less expensive, but also less efficient technology than other solar power.

Crider said the company hasn't decided yet whether the Kern County project will also rely on thin-film solar or other forms. For instance, some utility-scale projects can use solar panels that rely on lenses or mirrors to concentrate rays onto highly-efficient solar cells, and have tracking systems to follow the sun across the sky.

Another key aspect of Sempra's project is that it will be built on former grazing land near existing power lines, so it doesn't require new transmission lines or tearing up pristine desert.

"With careful site selection, we can get the benefits of green energy with very little impacts on the environment," Crider said.

Once a deal with a utility is struck the project will require approval from the California Public Utilities Commission, Crider said.